Engine starter



W. L. MGRATH ENGINE STARTER Filed Nv.15, 192s 2 sheets-sheet 1v Nov. 29, 1927. 1,650,639

w. L. MCGRATH ENGINE STARTER Filed Nov. 15, 1923 2 Sheets-Sheet 2 winnaar L.. MGGRATH, or nmviiaii, NEW YORK,

oOMPANY, or nimma, NEW YORK, A CORPORATION or Nnw YORK.

nNo'rINE ASSIGNOR TO ECLIPSE MACHINE STARTER.

Application led November 15, 1923. Serial No. 674,899.

My invention relates to engine starters for the starting of engines such as aninternal combustion engine, and more particularly Ato that part of such system known as the drive or transmission which transmitspthe power of aprime mover such as an elect-ric motor to a member of the engine to be started such as the flywheel thereof. AInthe present embodiment of my invention, a drivi ing memberA such as a pinion isl adapted to 'be manually meshed with the flywheel and to be automatically disengaged therefrom f when the vengine starts on its own power.

This pinion is adapted to be subjected to a yielding pressure such as spring pressure and the object of my invention is to provide for the pinion a spring pressure which shall be variable according to the different phases of operation inthe cycle of operation of the'drive. ln particular, the spring means is adapted to exert its maximum pressure against the pinion for the purpose of u returning the same to a normal position after being disengaged fromv the iiywheel and its minimum pressure (according to one form), or none at all (according to another form), at the time when the engine starts on its own disengaged.

ln the drawings, Figure 1 is a sectional elevation of a starting system embodying 'my invention showing the normal or disengaged position of the parts in full lines and the operated or engaged position in dotted lines; Fig. 2 is a similar view but illustrating cranking position with the spring withdrawn and before disengagement of the pinion; Fig. 3 a sectional elevation illustrating `cranking position before theA spring is withdrawn from the pinion; Fig. 4 a detail View of one of the spring abutments; Fig. 5 a

sideviewof one of the springs; Fig.v 6 a plan View thereof; Fig. 7 a section of thel pinion; Fig. 8 a sectional elevation of a modified form of Construction; and Fig. 9 a detail View ofone of the spring abutments alone.I l For the sake of a clear and definite dcscription of myinvention, I have shown the saine incorporated in a drive of the outboard type and also ofthe direct drivetype, but it will be understood that such invention is applicable also to the inboard type and also to the indirect type of. drive.

Referring .to the particular embodment power andthe pinion is being.

of my invention as shown in Figs. 1 -to '7, the prime mover is here an electric motor 1 havingan extended armature shaft 2 provided at its outer end with a suitable bearing 3. A hollow7 shaft or sleeve 4 ismounted upon the driving or armature shaft. for longitudinal movement thereof and rotary movement therewith through the medium of longitudinal splines 5 on the armature shaft which are engaged by the bore of the hollow shaft. This lattershaft is provided with screw threads '6 and may,l therefore, be called a screw shaft. This screw shaft is provided at its inner end as -a separate or integral part thereof with a sleeve extension having between them a circumferential 'oove' 8 with which cooperates a roller 9 o a shiftparallel flanges 7, forming' ing means which may be of any suitable pivoted at 11 and actuated by the operatorby hand or foot. A

The driving member is here in the form `of a pinion 12 which is-adapted to mesh with the teeth of the engine iiywheel 13. It is threaded upon the screw shaft for longitudinal movement thereof and rotary movement therewith and is normally held sp pressed `against a sto nut 14 at the outer end of the screw sha t. The spring means, about'to be described, cooperates with the pinion in the manner stated and also to return the pinion to normal position against the stop nut after being automatically demeshed from the flywheel.A The Object of my invention is to provide a spring means which shall perform these functions and at the same time not interfere with the freedom of movement of the pinion during its demeshing operation.

To this end, I `provide a series of springs 15 which are looped at-their centers around the grooved middle portions of weighted buttons 16 in the form of small dumb-bells. The outer ends of these springs are connected lin a suitable way as by means of pivot pins 17 to two spring abutment 18 and 19 respectively. The plate 18 1s adjacent the inner face of the pinion 12 and when the parts are in the normal position as shown infull lines in Fig. 1 such plate bears with a light pressure against the pinion and holds the same in its normal position against the stop nut 14. The other plate 19 lits over the screw shaft and is ringl plates pgsitioned against a drum or flange sleeve M drive also includes means for catchingv and olding the pinion in retracted position on the screw shaft after being demeshed from the fiywheel and preventing the pinion from contacting the flywheel in case the screw shaft should be left in shifted position after the engine has been started. Such means which are shown in Fig. 3, comprise a latch 21 pivoted in a longitudinal slot 22 in the -screw shaft and adapted to engage a notch.

23 in the bore of the pinion, Fig. 7. Norinally the outer end of the latch lies in a groove between twoof the splines 5 of the armature shaft and the inner end bears against the periphery of such armature shaft. 1When the screw shaft is shifted to the left the inner end of the latch will ride down the slope 24 at the inner end of such groove by reason of the pressure of the spring 25, with the result that the outer end of the latch will be moved radially to opera-l tive position to engage the notch 23 when the pinion is within the range of the latch'. Upon demesliing. the pinion moves longitudinally inwardly on the screw shaft and is caught by the latch and thereby prevented from returning to normal position until the latch is actuated to release it in theinanner hereinafter explained.

Describing a cycle of operation and beginning with the parts in their normal position shown in full lines in Fig. 1, the operator b diive assembly to the left. bringing the pinion-12 into mesh with the flywheel gear. Thereupon either by independent operation or automatically as an incident to the final operation of the shifting means` the current is supplied to the motor thereby rotating the screw shaft and its pinion and rotating the flywheel. Thereupon by centrifugal action tion. the. inner end the buttons 16 will be thrown outwardly and the springs and the plates 18 and 19` will assume the position shown in Fig. 2. In particular, the plate 18 will be. withdrawn from the path of demeshing movement of the. pinion with the result that the pinion is now free-to move to the right with perfect freedom when automatically deineshed as a result of the operation of the engine on its own power. The pinion will now be caught by the latch 21 and held in retracted positionY until the next phase of operation.

rl`hen when the shifting means is released the screw shaft will slide Yback to normal position, but just before it reaches that posiof its latch will ride up on the slope 24 and onto the periphery of the armature shaft.v thereby releasing the latch from the lpinion. At this time the springs 15 are at maximum tension and in their restoration to normal condition as the motor slows down, such springs will forciblyvthrust .sto nut.

llii Fi s.

actuating the shifting means shifts the 'the pinion to its normal position against the 8 and v9, I have shown a modified form o construction according to which pivoted arms Vcooperating with a coiled spring perform the function of the springs 15 above described. In this modified form, a series of links 21 are pivoted to each other at their adjacent ends and at their outer ends to plates 22 and 23. The plate 23 is adapted to slide freely upon the screw shaft and the same forms a movable abutment for a coil spring 24 which is interposed between it and a spring abutment 25 carried by the pinion. The links are held in normal extended position as shown in full lines in Fig. 8 by means of a truncated conical shell 26 which is secured within the casing 27. This casing forms the bearing forthe drive and also for the shifter mechanism and the same is attached to one end of the starting motor frame.

Describing a cycle of operation of the parts shown in Fig. 8 beginning with the same in their normal position shown in .full

lines the operator shifts the drive assembly' in the manner hereinbefore described, thereby bringing the pinion into mesh with the flywheel.' As a result of this movement, the pressure of the spring will buckle the links tothe dotted line position shown in Fig. 8 due to the relief from the shell 2G and the. pressure of the coil spring 24 against the abutment 23 thereby moving such abutment to the right against the edge of the drum 28. ln this manner, the pressure of the coil spring against the pinion will be relieved so that when the pinion is automatically deineslied it will not encounter any material resistance to its longitudinal movement` but when the operator releases the shifting means and the screw shaft is returned to normal position the shell 26 will straighten out the links to their normal position and as a result an increased pressure will be imparted to the 'pinion'by reason of the compression of the -tlic catch device for holding the pinion in .denieshed position while the screw shaft or sleeve isstill shifted to cranking position as the saine represent. subject matter of my prior applications for patent including application filed on January 4. 1923. Serial No. 610,672. the presentapplication being directed to the particular invention pointed `out in the claims herein.v

y I'claim:

LlAn engine starter drive including a rotatable shaft, a driving member mounted thereon for rotary movement therewith and for longitudinal movementJ thereof, yielding and centrifugal means acting upon the yield-V ing means for varying the degree of pressure exerted thereby on the driving member without affecting the position of the latter on the shaft.

3. An engine starter drive including a rotatable shaft, a driving member mounted thereon for rotaryl movement therewith and for'longitudinal movement thereof int-o engagement with a member of the engine to be started and for automatic disengagement therefrom, yielding means acting en the1 driving member tending to hold it to a nor; mal position on the shaft, and speed responsive means physically independent of the. driving member for varying the degree of pressure exerted by the yielding'mcans on the driving member.

4. An engine starter drive including a rotatable shaft, a driving member mounted thereon for rotary movement therewith and for longitudinal movement thereof into engagement with a member of the engine to be started and for automatic disengagement therefrom, yielding means acting on the driving member tending to hold it to a normal position on the shaft, and centrifuffal means physically independent of the driving member and acting upon the yielding means for varying the degree ofy pressure exerted thereby on the driving member.

An engine starter drive including a rotatable shaft, a driving member mounted thereon for rotary movement therewith and for longitudinal movement thereof, yielding means acting on the driving member tending to hold it to a normal 'position' onthe shaft, and comprising aspring, and speed responsive means cooperating therewith for varying the degree of pressure exerted thereby on the driving member without yaffecting the position ofthe latter on the shaft.

'6. An engine starter drive including u rotatable shaft, adriving member -mounted thereon for rotary movement therewith and for longitudinal movement thereof, yielding f means acting on the drivingmember tending to hold it to a normal position on the shaft, and comprising a spring, and a renf` for longitudinal trifugalv weightl cooperating therewith for varying the degree of pressure exerted thereby onthe` driving member without vaffectingtheposition ofthe latter on the.

y l 37o 7. An engine starterv drive including aro-` shaft.

tatable shaft, a .driving member mounted thereon for rotary-movement therewith and movement? thereof, yielding means acting onthe driving member tend- `mg to hold it toa normal posit-ionen the shaft, and comprising a series of springs mounted on the shaft, and centrifugally operating weights on said springs.- K

n engine starter drive including a,v ro'- tatable shaft, a driving member-mounted thereon for rotary movement therewith 'and for longitudinal movement thereof, yielding means acting on ing to hold it to a normal position on :the

the driving member tendshaft, and comprisineF a series ofV springs mounted on the sha t, a connected with one end of ment of the driving member, and speed responsive means for controlling said move! ment of the abutment. i I

9. Anengine starter drive including a rotatable shaft, a driving member mounted thereon for vrotary movement therewith and Ifor longitudinal movement thereof, yieldspring abutment'` l said springs and .movable longitudinally in the path of moveto hold it' to a normal position on the shaftl and comprising a series of springs mounted on the shaft and having vcenter loops, and weighted buttons fastened to said loops.

1l. An engine starter drive including av rotatable shaft, a driving member mounted thereon for rotary movement therewith and for longitudinal movement thereof, yielding means acting on the driving member tending to hold it to a normal position on the shaft and comprising a series of springs, two pal'- allel spring abiitnents, one o f which 1s rig-| idly secured to the shaft and the other of which `is movable longitudinally thereof. and centrifugally operating weights secured to said springs.

12. Anengine starter drive including a rotatable shaft, a driving member mounted thereon for rotary movement therewith and for longitudinal movement thereof, yielding Ella means acting on the driving member tending to hold it to a normal position on the shaft and comprising a series of springs, two parallel spring abiitments, one of which is rigidly secured to the shaft and the other of which is movable longitudinally thereof, said springs being pivotally attached at their ends to said abutments, and centrifugally operating weights secured to said springs.

13. An engine starter drive including a rotatable shaft, a driving member mounted thereon for rotary movement therewith and for longitudinal movement thereof, yielding means acting on the driving member tending to `hold it to a normal position on the Shaft and comprising spring means and a longitudinally movable spring abutment connected therewith and movable relative to the driving member, and speed responsive means for moving such abutment longitudinally and thereby varying the degree of pressure exerted by the spring means upon the driving member.

. 14. An engine starter drive including -a rotatable shaft, a driving member mounted thereon for rotary movement therewith and `for longitudinal movement thereof, yielding means acting on the driving member tending to-hold it to a normal position on the shaft and comprising spring means and a longitiidinally movable spring abutment connected therewith and lmovable relative tothe driving member, and eentrifugally operated weights cooperating with the abutmentland spring for varying the degree of pressure exerted by the spring means uponthe drivingmember. i

15. An engine starter drive' 'including a rotatable shaft, a driving member mounted thereon for rotary movement therewithand for longitudinal movement thereof, yielding vmeans acting on the driving member tending to hold it to a normal position on the shaft and comprising a spring and two spring abutments with which the spring cooperates, one of the abutments being secured to the shaft and the other movable longitudinally thereof, and speed responsive means cooperatin with' said spring. f

16. nengine starter drive incliidinga rotatable screw-threaded shaft, a pinion threaded thereon for' rotary movement thereofiand for longitudinal movement thereof and adapted to engage a member ofthe engine to be started, said shaft having a stop against which the pinion is normally positioned, and speed responsive yielding means adaptedto return the pinion to its said normal position but not interfering with its (lli longitudinal movement on the screw shaft in its demeshing operation.

17. An yengine starter drive including a rotatable shaft, a driving member mounted' thereon for rotary movement therewith Aand for longitudinal movement thereof, and

adapted to engage a member of the engine to be started, speed responsive controlled yielding means acting on the driving member to restore it to normal position on the shaft, and means forl temporarily holding the driving member in retracted position' on the shaft after its disengagement from the engine member.

18. An engine starter drive including a rotatable shaft, a driving ,member mounted thereon for rotary movement therewith and for longitudinal movement thereof, and adapted to engage a member of the engine to vbe started, speed responsive controlled yielding means acting on the driving member to restore it to normal position on the shaft, said shaft being mounted also for longitiidinal movement, -and means controlled by the longitudinal movement of the shaft for temporarily holding the driving member in retracted position on the shaft after its disengagement from the engine member.

19. An engine starter drive including a rotatable shaft, a driving member mounted thereon for rotary movement therewith and for longitudinal movement thereof, and adapted to engage a member of the engine to be started, speed responsive controlled yielding means acting on Ithe driving member to restore. it to normal position on the shaft, said shaft .being mounted also for longitudinal movement, and means controlled by the longitudinal movement of thg shaft for ltemporarily holding the driving member in I retracted position on the shaft after its disenfagement from the engine member, said lio ding means comprising a latch pivoted on thel shaft and, in its operative position adapted to engage the driving member when in rangp thereof.

20. n engine starter drive including a iotatable` screw-threaded shaft, a pinion threaded thereon for rotary moverrffvhereof and for longitudinal movement'thereof and adapted to engage a. member of the en- 'gine tothe started, said shaft having a stop against which the pinion is normally positioned, and speed responsive yielding means adapted to return the pinion to its said normal position but not interfering with its vlongitudinal movement on the screw shaft in its demeshng operation, and also including longitudinal movement on the screw shaft in its demeshing operation, and also including means for temporarily holding the pinion in retracted position on the shaft after disengagement, such holding means comprising a latch pivoted on the shaft, and, in its operative position adapted to engage.I the pinion whenV in range thereof. l

22. An engine starter drive including a rotatable shaft, a driving member mounted thereon for rotary movement therewith and for longitudinal movement thereof, yielding means acting on the driving member tending to hold it to a normal position on the shaft, and speed responsive means for removing the pressure ofsuch yielding means upon the driving member. l

23. An engine starter drive including a rotatable shaft, a driving member mounted thereon for rotary movement therewith and for longitudinal movement thereofLa longitudinally movable spring abutment, a coil spring bearing at one end against the driving member and tending to hold it to a normal position on the shaft and at its other end against said abutment, and `speed responsive means for controlling the longitudinal positionof such abutment for removing the pressure of 'the spring upon the, driving member.

24. An engine starter drive including a rotatable driving shaft, asleeve mounted to slide longitudinally upon said shaft and to be rotarilydriven thereby, yielding means acting von the driving member tending to 'hold it to a normalv position on the sleeve,

speed responsive means for removing the pressure of such yielding means upon the driving member, and meane'for sliding the sleeve upon said shaft WILLIM L. Moena'rn. 

